Grinding wheel truing apparatus



Jan. 29, 1946. H. A. SILVEN GRINDING WHEEL TRUING APPARATUS Filed Nov. 21, 1944 2 Sheets-Sheet 1 mmw HERBERT A. SILVEN l l l 1 Jan. 29, 1946. H. A. SILVEN GRINDING WHEEL TRUING APIARATUS Filed Nov. 21, 1944 2 Sheets-Sheet 2 HERBERT A. S/LVEN gwvcmto o Patented Jam. 29, 1946 UNITED STATES PATENT FFICE I 2,393,931 onnvnmo wnsa 'llRUING APrAna'rUs Herbert A. Silven. Worcester, Mass., assignor-to Norton Company, Worcester, Mass, a corporation of Massachusetts Application November 21, 1944, Serial No. 564,441

7 Claims. 01. 125-11) 'Ihis invention relates to grinding machines, and

more particularly to a grinding wheel truing apsively truing the plane operative faces of a pair of opposed grinding wheels with either plane or frusto-conical faces.

Another object of the invention is to provide a truing apparatus having two opposed truing tools arranged for successively trulng the operative faces of two opposed grinding wheels, in which the truing tools are maintained in a fixed position for a truing operation so that it is not necessary to reset the wheel positioning mechanism after the truing operation has been performed. Another object of the invention is to provide an adjusting mechanism to facilitate compensation for wear on the truing tools. Other objects will be apparent from the foregoing disclosure.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings in which is shown one of various possible embodiments of the mechanical features 01 this invention:

Fig. 1 is a front elevation of a hydraulically operated surface grinding machine, illustrating the improved truing apparatus; I

lfiig, 2 is a fragmentary front elevation, on an enlarged scale, of the improved truing apparatus;

Fig. 3 is a plan view of the truing apparatus on an enlarged scale;

Fig. 4 is a longitudinal sectional view, taken al proximately on the line IL-5! of Fig. 3, through the twins apparatus;

'Fig. 5 is a cross sectional view, on an enlarged scale, taken approximately on the line 5-5 of Fig. 3, showing the adjusting mechanism for one of the truhig tools; and

drawings comprising a base it which supports a longitudinally movable work table H on suitable slideways (not shown). A transversely movable table it is supported on slideways formed on the upper surface of the longitudinally movable table it, said slideways being arranged so that a work piece supported on-said transversely movable table niay be moved either longitudinally or transversely for a grinding operation. The base it is provided with an upwardly extending column 93 which supports a vertically movable grinding wheel slide it having suitable slideways formed between the slide it and the column E3. The slide it serves as a support for a vertically arranged grinding wheel spindle it which in turn supports a pair of'spaced grinding Wheels it and Fig. 6 is a fragmentary diagrammatic view,

showing the relationship of the truing tool and the grinding wheels.

A grinding machine has been illustrated in the ll, the grinding wheels it and ii being arranged successively to grind an upper and a lower surface on a work piece it. The work piece it is provided with a plurality of webbed portions it I having upper and lower parallel plane surfaces to be ground to a predetermined extent.

Grinding wheel feed The wheel slide it is preferably hydraulically controlled by means of a cylinder 20 which is fixedly mounted within the column it. A slide ably mounted piston 28 is provided in the cylinder 20 and is fixedly connected to a double end piston rod 22. The piston rod 22 extends through the end caps formed on the opposed ends of the cylinder 2d. The upper end of the piston rod 22 is fixedly connected to a bracket 23 which is in turn fixedly mounted on the vertically movable wheel slide it.

A manually operable control lever 25 is provided for actuating a control valve (not shown) to admit fluid either through a pipe 26 or through a pipe 2')? into the cylinder 2t to cause the piston 29 and the wheel slide it to moveeither upwardly or downwardly, depending upon the direction of movement of the control lever 25.

. The machine is arranged so that the grinding wheels it and it may be precisely positioned first to grind the upper surfaces of the webs it and then to grind the lower surface-s thereon. At the start of a grinding operation. the wheel slide it is moved downwardly to position the wheel it for grinding the upper surfaces of the webs, after which thewheel slide it is moved upwardly to position the wheel ill for grinding the under surfaces of the webs it. It is desirable to provide a suitable stop mechanism for each of the grinding wheels for precisely determining the up and 'doWn positions of the wheel slide M o that the wheels I8 and I1 may be precisely positioned forend of a rotatable shaft 33, A manually operable feed wheel 34 is mounted on the outer end of the shaft 33 and is provided with a standard micrometer feed adjusting mechanism 35 which is common and well known inthe grinding art. This micrometer adjusting mechanism is substantially the same as that shown in the expired patent to C. H. Norton, No. 762,838 dated June 14, 1904. The feed wheel 34 is provided with a stop abutment (not shown) by means of which the feed wheel may be turned to a predetermined position precisely to adjust the position of the upper wheel l6. Rotation of the feed wheel 34 serves to transmit a rotary motion to the sleeve 3| precisely to position the sleeve 3| relative to the feed screw 30. The lower end of the sleeve 3| is arranged when moved in a down ard direction to engage the upper end cap of the cylinder 28 and serves as a positive stopto limit the down feeding movement of the wheel slide l4 precisely to position the wheel I5 relative to the work piece to be ground. To compensate for wear on the grinding wheel l6, it is merely necessary to adjust the hand feed wheel 34 to re-position the stop sleeve 3| so as to allow the wheel slide l8 and grinding wheel l8 to move to a slightly lower position.

A similar feeding mechanism is provided to control the upward feeding movement of the slide l4 and the grinding wheel H to position the grinding wheel H in a predetermined position relative to the surface of the work piece to be ground. The piston rod 22 is provided with a second feed screw 38. A stop sleeve 33 is threaded onto the feed screw 38.' A worm gear 48 surrounds the sleeve 38 and is slidably keyed to the outer peripheral surface thereof. A worm (not shown) formed on the inner end of the shaft 4| meshes with the worm gear 40. A manually operable feed wheel 42 is mounted on the outer end of the shaft 4| and is provided with the usual micrometer adjusting mechanism 43. The micrometer adjusting mechanism 43 is provided with a stop abutment which is arranged to engage a stop (not shown) mounted on the base of the machine for limiting the rotary movement of the feed wheel asoaoev grinding wheels l8 and IT may be successively trued to the desired and predeterminedextent. It is desirable to provide a truing mechanism in which the truing diamonds are fixed during normal operation of the machine so that after the grinding wheels have been trued, it is not necessary to reset the feeding mechanism before resuming the grinding operation. The diamonds are adjustable only to compensate for wear of the diamonds themselves. In the grinding operation illustrated in the present case, it is desirable that the operative faces of the grinding wheels be provided with or frusto-conical operative face which tapers toward the wheel spindle in a manner similar to that shown diagrammatically in Fig. 6.

A pair of diamonds or truing tools and 5| are provided to true the operative faces of the grinding wheels l6 and II, respectively." These diamonds are mounted in a manner to be hereinafter described and are arranged .-to be traversed in a direction such as illustrated by the line 53 (Fig. 6). This line is parallel to the face of the grinding wheel It to be trued by the diamond 58 and is also wheel H to be trued by the diamond 5|.

The truing mechanism has been illustrated in Figs. 2 to 6 inclusive. A frame 60 is fastened to the column l3 of the machine. This frame preferably comprises a pair of brackets 6| and 82 which are bolted to the main part 80 of the 42. When the wheel slide and grinding wheel I! I are moved in an upward direction, the feeding movement continues until the upper end of the sleeve 39' engages the end face of the lower cylinder cap which serves as a=positive stop to limit the upward feeding movement of the grinding wheel slide l4 precisely to position the operative face of the grinding wheel I! relative to the lower face of the work piece to be ground. It will be readily apparent from the foregoing disclosure that by adjusting the feed wheel 42, the position of the stop sleeve 38 may be readily adjusted so as to compensate for wear of the grinding wheel l1. v

It is desirable that a suitable truing apparatus be provided so that the opposed faces of the frame and each of these brackets GI and 52 is rigidly bolted to opposite side faces of the column |3. A plate 63 is pivotally supported on a stud 64 which is in turn fixedly mounted on the frame 60. The plate 63 may be clamped in adjusted position on the frame 88 by means of clamping screws 65, 65a, 68, 86a and 68b, respectively,

formed in the plate 83 and are screw threaded into the frame 68. It will be readily apparent from the foregoing disclosure that the'plate 53 which serves as a support for the truing apparatus may be angularly adjusted to determine the I path of movement of the truing tools 50 and 5| so that the truing tools may be moved either in a plane normal to the axis of rotation of the grind-v ing. wheels l6 and I! or at'an angle thereto, de-

pending upon whether a flat operative face or a tapered operative face is desired.

The plate 63 is provided with a pair of spaced bearing brackets I0 and 'I l The bearing bracket 18 rotatably supports one end of a longitudinally extending, rotatably adjustable sleeve 12 (Fig. 4) The sleeve 12 is supported within aconcentric .sleeve13 which is journalled in a bearing surface formed in the bracket 1| The sleeve I3 is provided with an adjustably mounted truing tool arm 14 which serves as a support for the truing tool or diamond 58. Similarly, the sleeve 12 is provided with a. truing tool arm 15 which serves as a support for the diamond or truing tool 5|.

In order to traverse the truing tools 58 and 5| successively across the operative faces of the grinding wheels l6 and II, respectively, a suitable traversing mechanism is provided comprising a manually operable hand wheel 88 which is mounted on the outer end of a feed screw shaft 8|. The feed screw shaft 8| is rotatably supported within the sleeve 12. The feed screw shaft 8| is provided with a threaded portion which meshes with a nut 83. The nut 83 is formed integral with a bracket 84 which is fixedly mounted to the bearing bracket Ill. It will be readily apparent from the foregoing disclosure that a rotary motion of the hand wheel will be a slightly back tapered parallel to the face of the grinding transmitted through the feed screw 82 and nut 83 to cause the feed screw shaft 8| together with the sleeves l2 and 13 to traverse longitudinally in an axial direction to traverse the truing tools and 5| across the operative faces of the grinding wheels l6 and IT.

The truing tools 50 and 5| are positioned so that when the grinding wheels l6 and H are successively positioned in operative grinding positions, the diamonds may be traversed across the faces thereof to true them as desired. If it is desired to true a thousandth of an inch off the face of the grinding wheel I 6, the feeding mechanism, that is, the feed wheel 34, is rotated to adjust the sleeve 3! relative to the feed screw 30 so that the grinding wheel i6 is fed-downwardly to a new position, after which the truing tool may be traversed across the face thereof. The trued face of the wheel i6 is then in position so that when grinding is resumed, no re-adjustment of the feed mechanism is necessary to feed the wheel downwardly to grind the surface of the work to the desired and predetermined extent. Similarly, when the lower wheel I! is trued, the feed wheel 42 may be turned to adjust the sleeve 39 relative to the screw 38 to reposition the grinding wheel I! for a truing operation.

It is desirable to provide a suitable mechanism normally to hold the sleeves l2 and 13 against rotation and to facilitate adjustment of the truing tools 5|] and 5| to compensate for diamond wear. An arm 90 is mounted on the outer end of the sleeve 12. Similarly, an arm 9| is mounted on the outer or right-hand end of the sleeve 13. The arms 90 and 9| are substantially identical in shape and are arranged to facilitate angular adjustment of the sleeves I Zand 13, respectively.

Since these arms are identical, only one of them.

has been illustrated in detail.

The bearing brackets l0 and II also serve as supports for a slidably mounted rod 92. The rod 92 extends through elongated rectangularly shaped openings 93 and 9 3 formed in the arms 99 and 9|, respectively. An adjusting screw 95 is screw. threaded into a portion 96 in the arm 90. The other end of the screw is rotatably supported in a bearing 97 formed in the arm 99. An

adjusting knob 98 is mounted on the outer end of the adjusting screw 95 to facilitate manual adjustment thereof. The screw 95 passes through an aperture 99 formed in therod 92. A fixed collar Hill is mounted on the screw 95 and bears against a plane surface milled on the side of the rod 92. A thrust collar |0| is slidably mounted on the other end of the screw 95 to facilitate manualadjustment thereof and bears I right-hand inner face of the aperture 93 of the arm 90. It will be readily apparent from the foregoing disclosure that a rotary adjustment of the knob 98 will be transmitted angularly to adjust the arm 90 relative to the fixed rod 92 so as to adjust the position of the diamond 5| which trues the lower wheel H. The knob 98 is provided with graduations I03 and an index mark I04 is fixedly mounted on the arm 90 to facilitate precise adjustment of the diamond 5! in setting up the machine and also to compensate for wear of the diamond 5|.

A similar screw (not shown) is provided for adjusting the arm 9| relative to the fixed rod 92. The details of this adjustment have not been illustrated since this mechanism is identical with off the faces of the grinding wheel; Hi and II,

respectively. After this adjustment has b en made, the hand wheel 89 is rotated to traverse he truing tools 5|) and 5| relative to the opera ive faces of the grinding wheels IS an( H, respectively, successively to true the operative faces thereof. The diamonds or truing tools 50 and 5| are not adjusted during use of the machine except to compensate for wear on the diamonds themselves.

The operation of this improved truing apparatus will be readily apparent from the foregoing disclosure. Assuming all the adjustments have been previously made, that is, the frame 53 has been adjusted to the desired angular position to determine the path of travel of the truing tools 59and 5| so that either a plane radial face may be trued or a tapered face may be trued as desired, the lever 25 is then shifted to cause a downward movement of the piston 2| to position the sleeve 3| against the upper end of the cylinder 29. The feed .wheel 34 may then be adjusted to feed the grinding wheel i5 downwardly by an amount equal to that desired to be trued off the face of the grinding wheel l6. The hand wheel may then be rotated to traverse the truing tool Ell-across the operative face of the grinding wheel it to true the same. During this truing operation, the diamond 5| is out of contact with the grinding wheel ll. After the grinding wheel it has been trued to the desired and predetermined extent, the lever 25 is again shifted to cause an upward movement-of the pis ton 2| and the wheel slide l4 toposition the stop sleeve= 39 against the lower end of the cylinder 20 so as to positionthe grinding wheel IT in a predetermined operative position. The feed wheel 42 may then be adjusted to move the wheel ll upwardly by an amount equal to that desired to be trued oil the operative face thereof. After this adjustment has been made, the hand wheel 80 may then be rotated to traverse the truing tool 5| .across the operative face of the grinding wheel 81 to true the operative face of said wheel. After these truing operations havebeen completed, the grinding operation may again be resumed without the necessity of re-adjusting the feed mechanisms to compensate for the truing operation.

It will thus be seen that there has been provided by this inventio apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood-that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a truing apparatus for truing the-plane operative face of a grinding wheel, means to loto traverse said sleeve in an axial direction to 4- traverse the truing tool across the face of said wheel, and means rotarily to adjust said sleeve to adjust the position of the truing tool so as to compensate for wear thereon.

'2. In a truing apparatus for truing the opposed faces of a pair of spaced grinding wheels, means to locate said wheels successively in predetermined grinding positions, a pair of truing tools, a pair of non-rotatable slidably-mounted concentric sleeves each of which is arranged independently to support one of said truing tools, said truing tools being positioned successively to true the operative faces of both of said grinding wheels when the grinding wheels are in a final grinding position,;means simultaneously to traverse said sleeves and truing tools, and means rotarily to adjust each of said sleeves independently to adjust the position of said truing tools so as to compensate for wear thereon.

3. In a truing apparatus for truing the opposed faces of a pair of spaced grinding wheels, means including a piston and cylinder to locate said wheels successively in predetermined grinding positions, a pair of truing tools, a pair of slidably-mounted non-rotatable coaxial sleeves each ofwhich is arranged to supportone of said truing tools, means including a manually operable rotatable nut and screw mechanism to traverse said sleeves longitudinally so as to traverse the truing tools across the operative faces of said wheels, and independent means angularly to adjust said sleeves so as to adjust the position of said truing tools to compensate for wear thereon.

4. In a truing apparatus for truing the opposed'faces of a pair of spaced grinding wheels, means to locate the wheels successively in predetermined positions, a pair of truing tools, a pair of non-rotatable slidably-mounted concentric sleeves each of which is arranged independently to support one of said truing tools, said truing tools being positioned successively to true the operative faces of both of said grinding wheels when the grinding wheels are in a final grinding position, a slidably mounted rod, connections between each of said sleeves and said rod normally to hold said sleeves against rotation, and a' micrometer adjusting mechanism associated with said connections to facilitate an independent rotary adjustment of each of said sleeves to adjust the position of said truing tools so as to compensate for wear thereon.

5. In a truing apparatus for truing the opposed faces of a pair of spaced grinding wheels,

means to locate the wheels successively in predetermined grinding positions, a pair of. truing tools, a pair of non-rotatable slidably-mounted concentric-sleeves each of which is arranged independently to support one of said truing tools,

means including a nut and screw mechanism simultaneously to traverse said sleeves and truing tools, a slidably mounted rod, an independent arm on each of said sleeves, and independent connections between each of said arms and said rod normally to hold said sleeves against rotation, said connections, including micrometer adjusting screws to facilitate a rotary adjustment of said sleeves to compensate for wear on the truing tools.

6. In a truing apparatus for truing the opposed faces of a pair of spaced grinding wheels,

' means to locate the wheels successively in predetermined grinding positions, a pair of truing tools, a pair of slidably-mounted non-rotatable coaxial sleeves independently to support each of said truing tools, means to traverse said sleeves simultaneously to traverse the truing tools successively across the operative faces of said wheels, independent means rotarily to adjust said sleeves to adjust the position of said truing tools so as to compensate for wear thereon, and an adjustably mounted frame to support said sleeves to facilitate adjustment of the path of movement of the truing tools so that either a plane or a tapered face may be produced on said wheels.

7. In a truing apparatus for truing the opposed faces of a pair of spaced grinding wheels, means to locate said wheels successively in predetermined grinding positions, a truing apparatus frame, a pair of spaced truing tools, a pair 4 of slidably-mounted non-rotatable coaxial sleeves independently to support each of said truing tools on said frame, means including a nut and screw mechanism to traverse said sleeves simultaneously to traverse said truing tools successively across the operative faces of said wheels, a slidably mounted rod on said frame, independent connections between each of said sleeves and said rod normally to hold said sleeves against rotation, said connections including micrometer adjusting screws to facilitate a rotary adjustment of said sleeves so as to compensate for wear on said truing tools, and means to adjust the posi-. tion of said frame to facilitate adjustment-of the path of movement of the truing tools so that either a plane or a tapered face may be produced on said wheels.

HERBERT A. SILVEN. 

